Nitro-substituted dioxolanes and their method of preparation



United States Patent 3,432,524 NITRO-SUBSTITUTED DIOXOLANES AND THEIRMETHOD OF PREPARATION Gustave B. Linden, Short Hills, N.J., assignor toAerojet- Glelneral Corporation, Azusa, Calif., a corporation of 0 io NoDrawing. Original application Nov. 26, 1963, Ser. No. 326,288, nowPatent No. 3,306,929, dated Feb. 27, 1967. Divided and this applicationNov. 4, 1966, Ser. No. 632,835

US. Cl. 260-3403 3 Claims Int. Cl. 'C07d 13/04 ABSTRACT OF THEDISCLOSURE This patent describes novel compounds of the formula whereinR is hydrocarbyl and R is hydrogen, lower alkyl, lower aryl, loweralkaryl or lower aralkyl; and their method of preparation by reacting adiol of the formula with a carbonyl compound of the formula 0 H R'GR inthe presence of an acid esterification catalyst. These compounds containa plurality of nitro groups and are inherently useful as highexplosives.

wherein R is hydrocarbyl, preferably lower alkyl having Patented Mar.11, 1969 The compounds of Formula I are prepared in accordance with thefollowing general reaction equation:

wherein R and R are as defined above.

According to Reaction II, it can be seen that the 5,5,5-trinitro-1,2-pentanediol is reacted with an aldehyde or ketone to form asubstituted -4(3',3',3'-trinitropropyl-1,3- dioxolane.

Illustrative compounds which are obtained by the practice of Reaction IItogether with the corresponding rea ant materials are set forth in thefollowing table.

The above reaction may optionally be carried out in any inert solvent,i.e., polar solvents such as water, methanol, ethanol, etc.; andnon-polar solvents, i.e., benzene, hexane, toluene, etc. The proportionsof the reactants employed in the reaction are not critical. Normally,stoichiometrically equivalent amounts are used since this results in themost economical utilization of the reactants. Thus, usually one mole ofalcohol is used per mole of ketone or aldehyde. The reaction temperatureshould normally be sufliciently high so that the reactants will dissolveto a substantial degree in the reaction medium, but in any event, thereaction temperature should be below the compositon temperature of thereactant. Normally, the reaction is conducted at a temperature betweenabout 0 C. and about 100 C. The most preferred temperature is from about+20 C. to about C. Pressure is not critical in this reaction. Therefore,while any pressure can be used, the reaction is. normally run underatmospheric pressure.

The above reaction is preferably conducted in the presence of aneffective catalytic amount of an acid esterification catalyst such ascupric sulfate or boron trifiuoride etherate.

3 EXAMPLE 1 Preparation of the 2,2-dimethyl-4(3',3',3'-trinitropropyl)-1,3-dioxolane The 5,5,5-trinitro-1,2-pentanediol (427 grams) wasdissolved in 1500 ml. acetone. This solution was stirred with 600 g.anhydrous powdered cupric sulfate and 3 ml. boron trifluoride etheratefor 20 hours. The copper sulfate was removed by filtration and theacetone was removed under reduced pressure. The residual oil wastransferred to a beaker and 600 ml. ice water was added with stirring.The oil crystallized instantly. The product was filtered, washedthoroughly with ice water, and dried in vacuo. The yield of moistproduct wasc 405 g., M.P. 34 to 35 C. This crude dioxolane was heated toboiling with 1300 ml. hexane on the steam bath and the nearly colorless,cloudy solution was decanted from a small layer of oil and water. Thehexane solution was clarified by shaking with 50 g. sodium sulfate andfiltering. The hexane solution was cooled and seeded and left in adeep-freeze overnight. The colorless product was collected by filtrationand dried in vacuo. The yield of 2,2dimethyl-4(3,3,3'-trinitropropyl)-l,3-dioxolane was 3.6 g., M.P. 38 to39 C.

When the foregoing example is twice repeated using first acetaldehydeand then benzophenone in lieu of acetone, good yields of2-methyl-4(3',3',3'-trinitropropyl)- 1,3-dioxolane and2,2-diphenyl-4(3',3,3'-trinitropropyl)- 1,3-dioxolane, respectively, areobtained.

The compounds of Formula I may be isolated in conventional manner byfiltration, evaporation, extraction and/ or distillation.

The compounds of Formula I, which contain a plurality of nitro groups,are inherently useful as high explosives. These compounds can also beused in any conventional explosive missile, projectile, rocket or thelike, as the main explosive charge. An example of such a missile isdescribed in US. Patent 2,470,162, issued May 17, 1949. One way of usingsuch high explosives in a device such as that disclosed in US. Patent2,470,162 is to absorb the liquid explosive in an absorbent materialsuch as cellulose, wood pulp, or sawdust. The resultant dynamitetypeexplosive can then be packed into the warhead of the missile. A chargethus prepared is sufficiently insensitive to withstand the shockentailed in the ejection of a shell from a gun barrel or a rocketlaunching tube under the pressure developed from ignition of apropellant charge, and can be caused to explode on operation of animpact or time-fuse mechanism firing a detonating explosive such as leadazide or mercury fulminate.

The acetals of this invention are also useful as fungicides.

This example describes a particular method of preparing a novelpropellant composition according to this invention from the followingingredients wherein 2,2-dimethyl4(3',3',3'-trinitropropyl)-1,3-dioxolane is one of the plasticizers.

EXAMPLE II The aluminum powder is stirred into about /3 of the requiredvolume of polypropylene glycol and glycerol monoricinoleate. The mixtureis prepared in a stainless steel container, using a copper-berylliumspatula. Mixing is continued for about ten minutes.

The aluminum slurry is added to a conventional mixer equipped withfacilities for heating, cooling, and vacuumizing the propellant mix. Thewalls of the aluminum slurry container are scraped thoroughly. Thecontainer is rinsed with /2 of the required volume of dioctyl azelateand the rinses are added to the mixer. The remaining polypropyleneglycol is added to the mixer. The 2,2-dimethyl-4(3,3',3-trinitropropyl)-l,3-dioxolane is mixed with the remainingdioctyl azelate until homogeneous and the solution is then added to themixer.

With the mixer off, the ferric acetylacetonate, phenylbenanaphthylamine, and lecithin are added through a 40- mesh screen. Thecopper chromite is added to the mixer.

The mixer is covered and mixed by remote control for 15 minutes under 26to 28 inches of vacuum, after which it is stopped and the vacuumreleased with dry nitrogen. The cover is removed from the mixer and theoxidizer is added by remote control with the mixer blades in motion.

After all of the oxidizer has been added, the mixer is stopped andscraped down. The propellant mass is mixed for 15 minutes at 7 0 F. and2 6 inches vacuum by remote control. The mixer is stopped and the vacuumreleased with dry nitrogen. The tolylene diisocyanate is added, afterwhich the mass is mixed for ten minutes at 70 F. and 26 inches of vacuumby remote control. The vacuum is released with dry nitrogen and themixture is cast.

It will be understood that various modifications may be made in thisinvention without departing from the spirit thereof.

I claim:

1. A compound having the formula:

NO: /OC H-CHr-CHr-Af-NO:

wherein R is lower alkyl and aryl of 6 to 12 carbon atoms, and R isselected from the group consisting of hydrogen, lower alkyl and aryl of6 to 12 carbon atoms.

2. A compound having the formula:

Boekelheide et al., Journal of American Chemical Society, vol. 71(1949), pp. 3304-3307.

ALEX MAZEL, Primary Examiner.

JAMES H. TURNIPSEED, Assistant Examiner.

US. Cl. X.R. 149038; 260999

